Fix Menu Scroll Jump Issue in Hub Menu

[pmusolino]

Closes: #12640

Description

Users experienced an unexpected "bump" to the top of the menu view when attempting to scroll down. This issue, in reality, happens every time a user accesses the Hub Menu, and then navigates to the sub-settings views, and then presses back.

Testing instructions

1. Open the app and tap on the Menu.
2. Navigate to one of the settings.
3. Press back.
4. Scroll down on the Hub menu.

Changes Made:

• Removed the .toolbar(.hidden, for: .navigationBar) modifier from the HubMenu view, which was causing the navigation bar to be hidden also if it was already hidden and affecting the layout of the list.
• Cleaned up and simplified the code by removing unnecessary comments and adjustments related to list row separator alignment that were no longer needed from iOS 16 (unrelated to this bug).
• Ensured the navigation bar is hidden on the HubMenuViewController to maintain a consistent layout and avoid the scroll jumping issue. Removed viewWillDisappear since it was never called after migrating the view to SwiftUI.

Video

Before	After

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• [x] I have considered if this change warrants user-facing release notes and have added them to RELEASE-NOTES.txt if necessary.

[wpmobilebot]

📲 You can test the changes from this Pull Request in WooCommerce iOS by scanning the QR code below to install the corresponding build.

	App Name	WooCommerce iOS
	Build Number	pr12644-977a421
	Version	18.4
	Bundle ID	com.automattic.alpha.woocommerce
	Commit	977a421ecd75ef652b1549ba6ebcdd42f3dede54
	App Center Build	WooCommerce - Prototype Builds #8949

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